OYSTER BOTTOMS OF MISSISSIPPI EAST OF BILOXI. 27 



where. There appear to be three conceivable explanations of this 

 preponderance — (a) an extraordinary set of spat in the year preceding 

 the survey follo^^-ing the destruction of the beds by freshets or other 

 causes, (h) an unusually heavy set of spat without the destruction 

 of the mature oysters, and (c) an average condition witli respect to 

 spat production, but general conditions of environment which prevent 

 or retard the normal growth of the oysters. 



Judging from the appearance of the reefs and such information as 

 it was possible to obtain concerning their history it appears that the 

 third is the true explanation of the unsatisfactory state of the oysters. 

 While the spatting conditions are good there is apparently a deficiency 

 of the food requisite for the growth and fattening of the dense oyster 

 population. The oysters are crowded in clusters and the individuals 

 are unable to secure the requisite amount of nutriment. The planting 

 of oysters on the bottom adjoining the original bed of Scranton Reef 

 accentuated the trouble and was ill advised. Better success probably 

 would have attended planting in deeper water and where the tidal 

 flow is stronger. 



These beds densely crowded with small and inferior oysters are of no 

 immediate commercial value. Apparently their onl}^ use is for seed 

 beds from which the small oysters might be transplanted to localities 

 more favorable for growth. 



BARREN BOTTOMS. 



The area of barren bottoms — that is, those which are not naturally 

 productive of oysters even in small quantities — vastly exceeds that of 

 the natural beds, including in the latter those so-called depleted areas 

 which bear practically nothing. These bottoms are barren, mainly 

 because of one character in which they differ from the productive 

 areas — namely, that they are devoid of shells or other objects lying on 

 the surface. They consist of sand and mud of varying degrees of 

 stability and consistency. Oysters, immediately after they develop 

 from the egg, for a brief period swim or float freely in the water, 

 settling to a fixed condition only after they reach a stage of consid- 

 erable development.*^ 



It is not necessary to give more detail to this subject other than to 

 say that at the time at which they are undergoing fixation the oysters 

 are very minute, and a slight film of mud or slime is sufficient to stifle 

 them. During the spawTiing season these little organisms are present 

 in the water in untold myriads and are precipitated to the bottom in 

 a continuous gentle drizzle of tiny specks. If they fall on an oyster 

 bed they find firm supports on the shells and oysters, attach them- 

 selves and grow, but if they fall on the mud or bare sand they die. 



a For a more extended account see "Oyisters and methods of oyster culture," by H. F. Moore, Bureau 

 of Fisheries Document 349, which may be obtained by application to the Bureau at Washington, D. C. 



